I'm writing unit tests on some code that deals with the filesystem, and I'd like to demonstrate the code path works when close $fh or die $! fails. Any suggestions on how to trigger a failure in close()?

The first idea that occurs to me is to create a tiny loopback filesystem and write too many bytes to it and try to close it, but I'm wondering if there's an easier way.

I was hoping I could do local *other::package::close = sub { return 0 } in my test, but that doesn't take at all.

In reply to how to make close() fail by kgoess

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